High-Efficiency Lighting Systems and Networked Lighting Controls

What are High-Efficiency Lighting Systems and NLCs?

A high-efficiency lighting system integrates daylighting and energy efficient electrical lighting with networked lighting controls (NLCs), to provide a comfortable environment for occupants while reducing energy usage and costs (see Daylighting, and Smart Sensors and Controls).[1] Lighting accounts for 17% of the total electricity consumption in commercial buildings and contributes to a building’s cooling load by emitting waste heat.[2] More stringent building codes, a phasing out of traditional lighting technologies (e.g., incandescents), utility incentives and rebates, and more energy efficient federal standards for lighting applications (e.g., screw-in light bulbs) have helped to drive the market for energy-efficient lighting technologies.[3]

For example, fluorescent and high emitting diodes (HIDs) replaced incandescents, regarding energy efficiency and performance in the same way that LEDs (light emitting diodes) promise to command the commercial building sector, as LED technology and performance advance beyond screw-based fixtures to linear fixtures.[4] Fig 1 shows an OLED (organic light emitting diode), an emerging lighting technology, which utilizes carbon-based materials and can be molded into a variety of thin-profile configurations such as tiles and window-like materials to provide diffuse light.[5] OLEDs hold the potential to outperform LEDs as the technology commercializes and costs decline. Advances in materials, optics, electronic design, and smart sensors and controls, including lighting technologies paired with networked lighting controls, promise to offer additional performance and efficiency gains and an enhanced occupant experience through daylight harvesting, vacancy sensing, and task tuning. [6] By providing a foundation for future applications of the IoT (Internet of Things), networked lighting controls may also hold the potential to create new benefits and functions beyond supplying basic illumination, such as enhanced security, indoor environmental quality monitoring, and remote maintenance and service (see Smart Sensors and Controls).[7]

Figure 1. OLED Office Lighting (Source: US DOE Solid-State Lighting Program)

How to Incorporate a High-Efficiency Lighting System and NCLs?

Upgrading to high-efficiency lighting systems and NCLs in existing buildings involves complex interactions among multiple building systems and disciplines, requiring an integrated design process (see Integrated Design Process). For example, window glazing influences interior electrical lighting design, sizing of mechanical systems, and interior design layouts (see Windows and Skylights, Glare and Heat Gain Reduction, and Properly-Sized, High-Performance HVAC Equipment and Controls). Renovations also provide an opportunity to assess current natural light and electrical lighting levels and identify opportunities for improvement.

The first step to a high-efficiency lighting upgrade is to conduct a lighting audit or survey that establishes information about all the lighting technologies and consumption patterns in a building. Hire a lighting specialist and/or use Energy Star Portfolio Manager to benchmark energy usage and identify lighting upgrade opportunities. Based on the study, identify suitable replacement solutions including lamps, luminaires, and controls, and devise an implementation program.

Lighting upgrade guidelines, such as the EnergyStar Building Upgrade Manual Chapter 6: Lighting, provide general principles and examples, but project specific solutions often require hiring a daylighting and lighting expert familiar with advanced computer simulation software and tools that can effectively simulate a range of scenarios and outcomes.[8]

The following provides general best practice guidance on how to optimize daylighting and electrical lighting in existing commercial buildings.[9]

1. Set a Maximum Lighting Power Density (LPD) goal to avoid overlit spaces and to achieve an appropriate level of lighting per area lit or watts per square foot.
2. Set a Daylight Sufficiency Goal that establishes the amount of daylighting, measured in lumens or foot-candles, required to perform a typical task in each space without electrical lighting.
3. Develop a layered lighting strategy that first utilizes daylight to provide primary or ambient lighting levels, and then adds electrical lighting options and controls to vary lighting levels for a variety of tasks and occupant preferences.
4. Specify lighting products from the DesignLights Consortium or ENERGY STAR qualified product lists.
5. Use vacancy sensors (manual on, automatic off) as opposed to occupancy sensors (automatic on, automatic off) to save energy by requiring occupants to flip a switch if they require additional light.
6. Provide adjustable task lighting at individual workspaces to save energy by directing appropriate lighting to specific tasks.
7. Incorporate exterior motion sensors to save energy and enhance security and safety.
8. Consider photo-luminescent egress signage subject to local fire code.
9. Plan for backup power for critical lighting needs during a power outage, such as emergency and night-time lighting (see Energy Storage and Backup Power Generation).
10. Commission and regularly re-commission all lighting systems and controls to optimize performance and energy savings.

Examples

GSA Proving Ground – TLED Lighting Retrofits with Dedicated Drives

This case study conducted by the Pacific Northwest National Laboratory (PNNL) looked at the energy saving benefits of replacing Linear Fluorescent Lamps (LFLs) with Light-Emitting Diode (LED) lamps and with Advanced Lighting Controls (ALCs), such as dimming and occupancy sensing that do not require modifications to the existing ceiling for installation. The study found LED energy savings ranging from 27%-29% when LEDs replaced T8 LFLs with electronic ballasts.

Benefits

Supplementing natural daylight with high-efficiency lighting systems and NLCs provides multiple benefits:

• Reduced operating costs through energy efficiency gains and reduced maintenance and replacement costs through longer-lasting bulbs and fixtures.[10]
• Reduced cooling loads and downsized HVAC systems through less heat gain from electrical lighting (see Properly-Sized, High-Performance HVAC Equipment and Controls).[11]
• Reduced number of toxic chemicals released into the waste stream and reduced light pollution.
• Improved employee productivity and satisfaction based on a shared preference for naturally daylit spaces, reinforcement of circadian rhythms, and connection to nature.[12]
• Above average lease rates and lower tenant turnover.[13]

Costs

High-efficiency lighting design and NLCs should not impose a significant impact to project costs if considered early in the design phase and integrated throughout the design process. The costs of hiring an expert daylighting consultant and electrical lighting designer often pay for themselves through electrical lighting reductions and associated energy cost savings.

The table below shows costs for Commercial and Industrial LED Luminaries[14]

Table 1 – Commercial and Industrial Luminaries

Check the New Jersey Office of Clean Energy for available incentives. At the time of this writing, incentives for lighting controls range from $20-$45 per fixture. The incentives for performance lighting are $1.00 per watt below the allowable wattage as determined by ASHRAE 90.1-2013 baseline and $30 per eligible fixture. Prescriptive lighting incentives range from $5 to $150 per fixture.

Resiliency

Implementing high-efficiency lighting and NCLs provides energy savings and reduces reliance and stress on the electricity grid. Daylit-optimized buildings paired with high-efficiency lighting systems and built-in backup power for critical lighting needs further reduce stress on the grid, especially in the event of a power outage.

[1] Whole Building Design Guide. (WBDG). Energy Efficient Lighting. http://www.wbdg.org/resources/efficientlighting.php (accessed May 16, 2018).

[2] US Energy Information Administration (EIA). 2017. CBECS 2012 – Trends in Lighting in Commercial Buildings.

[3] The Energy Independence and Security Act (EISA) requires general service lighting products sold as of January 1, 2020, to have an efficacy of at least 45 lumens per watt.

[4] US DOE. 2017. “Guiding SSL Technology Advances.” Department of Solid-State Lighting. https://www.energy.gov/sites/prod/files/2016/09/f33/guiding-ssl-technology-advances_sep2016.pdf (accessed Dec 13, 2018).

[5] US DOE. 2017. OLED Basics. Department of Solid-State Lighting. https://www.energy.gov/eere/ssl/oled-basics (accessed Dec 13, 2018).

[6] US DOE. 2017. “Guiding SSL Technology Advances.” Department of Solid-State Lighting. https://www.energy.gov/sites/prod/files/2016/09/f33/guiding-ssl-technology-advances_sep2016.pdf (accessed Dec 13, 2018).

[7] Iain Campbell et al. 2017. “A New Way to Think About Office Lighting.” Harvard Business Review. Rocky Mountain Institute (RMI) Buildings Program. https://hbr.org/2017/06/a-new-way-to-think-about-office-lighting (accessed Dec 13, 2018).

[8] WBDG. Daylighting. http://www.wbdg.org/resources/daylighting.php (accessed April 4, 2018).

[9] General Service Administration (GSA) Office of Federal High-Performance Green Buildings. 2018. “Saving Energy Through Lighting and Daylighting Strategies.” https://www.gsa.gov/cdnstatic/Lighting_and_Daylighting_Two_Pager_508_compliant_2-9-15.pdf  (accessed Dec 11, 2018).

[10] Ibid WBDG.

[11] Efficient Windows Collaborative. 2018. Daylight Controls. Windows for High-Performance Buildings. http://www.commercialwindows.org/daycontrols.php (accessed July 5, 2018).

[12] California Energy Commission and Heschong Mahone Group. 2013 “Office Daylighting Potential”

http://www.sunlightindoors.com/resources/SunlightBenefits/OfficeDaylightPotential.pdf (accessed April 5, 2018).

[13] Daylight Dividends, Rensselaer Polytechnic Institute. “Daylighting Resources – Productivity.” http://www.lrc.rpi.edu/programs/daylighting/dr_productivity.asp (accessed April 4, 2018).

[14] US DOE: Energy Savers. “Purchasing Energy-Efficient Commercial and Industrial LED Luminaires.” https://www.energy.gov/eere/femp/purchasing-energy-efficient-commercial-and-industrial-led-luminaires (accessed May 18, 2018).

[15] The Best Available Model category is calculated based on the most efficient model in the database collected from manufacturers as of February 2017.

[16] The Required Model category is calculated based on new FEMP designated efficiency requirements. Federal agencies must purchase products that meet or exceed FEMP designated efficiency requirements.

[17] The Less Efficient Model category is calculated based on the previous FEMP requirement for this product type.